The present invention relates to a large capacity storage or mass storage. More particularly, it concerns a storage system that provides a high density, a high-speed data transfer rate, and a shorter access time simultaneously.
A conventional magnetic disk storage system is a reliable storage system capable of reading massive amounts of data at a high speed. The conventional magnetic disk storage system performs a reading or writing operation or a seeking operation wherein a disk-like magnetic recording medium is rotated at a high speed, and a slider having a magnetic head element incorporated therein is floated above the magnetic recording medium by a gimbal and an arm. The volume of the magnetic disk storage system having the disk-like magnetic recording medium is determined by the diameter of the disk and the dimensions of a head drive system comprising the gimbal, the arm, and similar devices. To make the system smaller first , the diameter of the magnetic recording medium has to be made smaller first. Then, since a recording area for data on the magnetic recording medium has to be made as wide as possible, a spindle motor for rotating the magnetic recording medium has to be made smaller.
For the smaller magnetic recording medium, a rotational frequency of the spindle motor must be increased. If not, a speed of the head relative to the medium is decreased, resulting in a problem that the data transfer rate is decreased. To solve the problem, the spindle motor has to be rotated at a very high speed. To store as much data as possible in the limited area, a track width for the data has to be made narrower. This necessitates a highly accurate rotation of the magnetic recording medium to suppress its possible eccentricity during rotation. Note that the system cannot be made small unless the spindle motor is made as thin as possible. However, technical considerations place limits on how small the spindle motor can be made. Also, mechanical stiffness requirements and production costs place limits on how small a head seeking arrangement including the gimbal and the arm system for accurately moving the magnetic head to a desired track on the magnetic recording medium can be made.
In view of the foregoing, it is an object of the present invention to provide a storage system that can be truly small sized with a capability of storing data at a high density by way of solving the problems involved in the prior art discussed above and presenting measures to overcome technical difficulties to be further considered.
Briefly, the foregoing object is accomplished in accordance with aspects of the present invention by a storage system. The storage system is capable of storing, transferring, and accessing massive amounts of data at high speed in a way-that a recording medium or a read/write device can be moved at high speed and accuracy, seek time can be made shorter, and spacing between the recording medium and the read/write device can be narrower without using the disk-like magnetic recording medium.
The present invention provides a first feature in that (1) a magnetic storage system for making data reading or writing or both, wherein a data write/record device or a magnetic recording medium or both is reciprocated from position to position relatively different with both being kept to a predetermined distance; (2) the magnetic storage system of item 1 mentioned above wherein the data read/write device or the magnetic recording medium or both is driven by any of an arrangement for converting a rotation to reciprocal motion, a piezo device, and quartz crystal; (3) the magnetic storage system of item 1 mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, is reciprocated along the recorded bits while the read/write device is made still or to follow the recorded bits; (4) the magnetic storage system of item 1 mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, the read/write device is reciprocated along the recorded bits while the magnetic recording medium is made still or to follow the recorded bits; (5) the magnetic storage system of item 1 mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, the read/write device and the magnetic recording medium are reciprocated opposite to each other along the recorded bits while the read/write device or the magnetic recording medium is made to follow the recorded bits; (6) the magnetic storage system of item 1 mentioned above wherein the magnetic recording medium has a zigzag series of recorded bits aligned thereon and in a reading or writing mode of operation, the read/write device and the magnetic recording medium are reciprocated in their respective directions not in parallel to each other along the recorded bits; (7) the magnetic storage system of item 1 mentioned above wherein a plurality of the read/write devices are regularly provided on a two-dimensional plane; (8) the magnetic storage system of item 1 mentioned above wherein seeking is made by a one-dimensional motion of the read/write device; (9) the magnetic storage system of item 1 mentioned above wherein seeking is made by a two-dimensional motion of the read/write device; (10) the magnetic storage system of item 1 mentioned above wherein seeking is made by combination of a one-dimensional motion of the read/write device and a one-dimensional motion of the magnetic recording medium; (11) the magnetic storage system of item 1 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium; (12) the magnetic storage system of item 1 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic recording medium; and, (13) the magnetic storage system of item 1 mentioned above wherein the read/write device and the magnetic recording medium are made to contact each other through or not through a lubricant by a predetermined force.
The present invention provides a second feature in that (14) a magnetic storage system having a magnetic head and a magnetic recording medium combined for reading or writing a magnetic signal as data source mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, the magnetic recording medium is moved in a simple harmonic motion along the recorded bits while the magnetic head is made still or to follow a track; (15) the magnetic storage system of item 14 mentioned above wherein the magnetic head is a multi-head having a plurality of read/write devices regularly aligned on a plane; (16) the magnetic storage system of item 14 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the track width direction; (17) the magnetic storage system of item 14 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the recording bit direction; (18) the magnetic storage system of item 14 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic head in the recording bit direction and the track width direction; (19) the magnetic storage system of item 14 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the recording bit direction and a one-dimensional motion of the magnetic recording medium in the track width direction; (20) the magnetic storage system of item 14 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the track width direction and a one-dimensional motion of the magnetic recording medium in the recording bit direction; (21) the magnetic storage system of item 14 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the track width direction; (22) the magnetic storage system of item 14 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the recording bit direction; (23) the magnetic storage system of item 14 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic recording medium in the recording bit direction and the track width direction; (24) the magnetic storage system of item 14 mentioned above wherein a piezo device prompts a reciprocal motion of the magnetic recording medium or the magnetic head in the recording bit direction in the reading or writing mode of operation or prompts a motion of the magnetic head or the magnetic recording medium among adjacent elements of the magnetic head in the track width direction in a seeking operation; (25) the magnetic storage system of item 14 mentioned above wherein the magnetic recording medium is a square or polygon and has regular grooves formed on a surface thereof; (26) the magnetic storage system of item 25 mentioned above wherein the magnetic recording medium is formed on a Si substrate of single crystal and the regular grooves are formed by way of a chemical etching process with use of a crystalline orientation; (27) the magnetic storage system of item 25 mentioned above wherein the magnetic recording medium is for longitudinal magnetic recording or perpendicular magnetic recording and for the longitudinal magnetic recording, an easy axis is in parallel with the recording bit direction; (28) the magnetic storage system of item 14 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is based on position information written in between sectors of a single track; (29) the magnetic storage system of item 14 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is made in a way that the magnetic head has a semiconductor laser on a part thereof, a laser beam is incident on a surface of the magnetic recording medium, and a difference of a light emission condition of the semiconductor laser with presence or absence of a groove is converted to voltage change or a change of light intensity at a rear of the laser is detected; (30) the magnetic storage system of item 14 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation in a way that the magnetic head has at least one detecting needle mounted thereon, and the at least one detecting needle is brought close to a surface of the magnetic recording medium to detect a change of a tunneling current with presence or absence of a groove; (31) the magnetic storage system of item 14 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in a seeking operation is made in a way that a number of grooves on a surface of the medium is counted on the basis of a change of an emission condition of a semiconductor laser or a tunneling current with the magnetic head or the magnetic recording medium moving in the track width direction; (32) the magnetic storage system of item 14 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is controlled with use of at least one piezo device; (33) the magnetic storage system of item 14 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is different, or higher in the reading or writing mode of operation than in a seeking operation; (34) the magnetic storage system of item 14 mentioned above wherein a volume is not greater than 40 cc; (35) the magnetic storage system of item 14 mentioned above wherein a single set of the magnetic head and the magnetic recording medium has data transferred therein in parallel; (36) the magnetic storage system of item 14 mentioned above wherein a multiple of sets of the magnetic heads and the magnetic recording media have data transferred thereamong in parallel; (37) the magnetic storage system of item 14 mentioned above wherein a mean access time is not longer than 1 msec; and, (38) the magnetic storage system of item 14 mentioned above wherein a transfer rate is not slower than 30 Mbyte/sec.
The present invention provides a third feature in that (39) a magnetic storage system having a magnetic head and a magnetic recording medium combined for reading or writing a magnetic signal as data source mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, the magnetic head is moved in a simple harmonic motion along the recorded bits while the magnetic recording medium is made still or its track is made to follow the magnetic head; (40) the magnetic storage system of item 39 mentioned above wherein the magnetic head is a multi-head having a plurality of read/write devices regularly aligned on a plane; (41) the magnetic storage system of item 39 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the track width direction; (42) the magnetic storage system of item 39 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the recording bit direction; (43) the magnetic storage system of item 39 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic head in the recording bit direction and the track width direction; (44) the magnetic storage system of item 39 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the recording bit direction and a one-dimensional motion of the magnetic recording medium in the track width direction; (45) the magnetic storage system of item 39 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the track width direction and a one-dimensional motion of the magnetic recording medium in the recording bit direction; (46) the magnetic storage system of item 39 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the track width direction; (47) the magnetic storage system of item 39 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the recording bit direction; (48) the magnetic storage system of item 39 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic recording medium in the recording bit direction and the track width direction; (49) the magnetic storage system of item 39 mentioned above wherein a piezo device prompts a reciprocal motion of the magnetic recording medium or the magnetic head in the recording bit direction in the reading or writing mode of operation or prompts a motion of the magnetic head or the magnetic recording medium among adjacent elements of the magnetic head in the recording track direction in a seeking operation; (50) the magnetic storage system of item 39 mentioned above wherein the magnetic recording medium is a square or a polygon of similar polygons and has regular grooves formed on a surface thereof; (51) the magnetic storage system of item 50 mentioned above wherein the magnetic recording medium is formed on a Si substrate of single crystal and the regular grooves are formed by way of a chemical etching process with use of a crystalline orientation; (52) the magnetic storage system of item 50 mentioned above wherein the magnetic recording medium is for longitudinal magnetic recording or perpendicular magnetic recording and for the longitudinal magnetic recording, an easy axis is in parallel with the recording bit direction; (53) the magnetic storage system of item 39 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is based on position information written in between sectors of a single track; (54) the magnetic storage system of item 39 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is made in a way that the magnetic head has a semiconductor laser on a part thereof, a laser beam is incident on a surface of the magnetic recording medium, and a difference of a light emission condition of the semiconductor laser with presence or absence of a groove is converted to voltage change or a change of light intensity at a rear of the laser is detected; (55) the magnetic storage system of item 39 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation in a way that the magnetic head has at least one detecting needle mounted thereon, and the at least one detecting needle is brought close to a surface of the magnetic recording medium to detect a change of a tunneling current with presence or absence of a groove; (56) the magnetic storage system of item 39 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in a seeking operation is made in a way that a number of grooves on a surface of the medium is counted on the basis of a change of an emission condition of a semiconductor laser or a tunneling current with the magnetic head or the magnetic recording medium moving in the track width direction; (57) the magnetic storage system of item 39 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is controlled with use of at least one piezo device; (58) the magnetic storage system of item 39 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is different, or higher in the reading or writing mode of operation than in a seeking operation; (59) the magnetic storage system of item 39 mentioned above wherein a volume is not greater than 40 cc; (60) the magnetic storage system of item 39 mentioned above wherein a single set of the magnetic head and the magnetic recording medium has data transferred therein in parallel; (61) the magnetic storage system of item 39 mentioned above wherein a multiple of sets of the magnetic heads and the magnetic recording media have data transferred thereamong in parallel; (62) the magnetic storage system of item 39 mentioned above wherein a mean access time is not longer than 1 msec; and, (63) the magnetic storage system of item 39 mentioned above wherein a transfer rate is not slower than 30 Mbyte/sec.
The present invention provides a fourth feature in that (64) a magnetic storage system having a magnetic head and a magnetic recording medium combined for reading or writing a magnetic signal as data source mentioned above wherein the magnetic recording medium has a linear or circular series of recorded bits aligned thereon and in a reading or writing mode of operation, the magnetic head and the magnetic recording medium are moved in a simple harmonic motion along the recorded bits at phases opposite to each other while either of the magnetic head or the magnetic recording medium is made to follow a track; (65) the magnetic storage system of item 64 mentioned above wherein the magnetic head is a multi-head having a plurality of read/write devices regularly aligned on a plane; (66) the magnetic storage system of item 64 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the track width direction; (67) the magnetic storage system of item 64 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the recording bit direction; (68) the magnetic storage system of item 64 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic head in the recording bit direction and the track width direction; (69) the magnetic storage system of item 64 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the recording bit direction and a one-dimensional motion of the magnetic recording medium in the track width direction; (70) the magnetic storage system of item 64 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the track width direction and a one-dimensional motion of the magnetic recording medium in the recording bit direction; (71) the magnetic storage system of item 64 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the track width direction; (72) the magnetic storage system of item 64 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the recording bit direction; (73) the magnetic storage system of item 64 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic recording medium in the recording bit direction and the track width direction; (74) the magnetic storage system of item 64 mentioned above wherein a piezo device prompts a reciprocal motion of the magnetic recording medium or the magnetic head in the recording bit direction in the reading or writing mode of operation or prompts a motion of the magnetic head or the magnetic recording medium among adjacent elements of the magnetic head in the track width direction in a seeking operation; (75) the magnetic storage system of item 64 mentioned above wherein the magnetic recording medium is a square or polygon and has regular grooves formed on a surface thereof; (76) the magnetic storage system of item 75 mentioned above wherein the magnetic recording medium is formed on a Si substrate of single crystal and the regular grooves are formed by way of a chemical etching process with use of a crystalline orientation; (77) the magnetic storage system of item 75 mentioned above wherein the magnetic recording medium is for longitudinal magnetic recording or perpendicular magnetic recording and for the longitudinal magnetic recording, an easy axis is in parallel with the recording bit direction; (78) the magnetic storage system of item 64 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is based on position information written in between sectors of a single track; (79) the magnetic storage system of item 64 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is made in a way that the magnetic head has a semiconductor laser on a part thereof, a laser beam is incident on a surface of the magnetic recording medium, and a difference of a light emission condition of the semiconductor laser with presence or absence of a groove is converted to voltage change or a change of light intensity at a rear of the laser is detected; (80) the magnetic storage system of item 64 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode,of operation in a way that the magnetic head has at least one detecting needle mounted thereon, and the at least one detecting needle is brought close to a surface of the magnetic recording medium to detect a change of a tunneling current with presence or absence of a groove; (81) the magnetic storage system of item 64 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in a seeking operation is made in a way that a number of grooves on a surface of the medium is counted on the basis of a change of an emission condition of a semiconductor laser or a tunneling current with the magnetic head or the magnetic recording medium moving in the track width direction; (82) the magnetic storage system of item 64 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is controlled with use of at least one piezo device, (83) the magnetic storage system of item 64 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is different, or higher in the reading or writing mode of operation than in a seeking operation; (84) the magnetic storage system of item 64 mentioned above wherein a volume is not greater than 40 cc; (85) the magnetic storage system of item 64 mentioned above wherein a single set of the magnetic head and the magnetic recording medium has data transferred therein in parallel; (86) the magnetic storage system of item 64 mentioned above wherein a multiple of sets of the magnetic heads and the magnetic recording media have data transferred thereamong in parallel; (87) the magnetic storage system of item 64 mentioned above wherein a mean access time is not longer than 1 msec; and, (88) the magnetic storage system of item 64 mentioned above wherein a transfer rate is not slower than 30 Mbyte/sec.
The present invention provides a fifth feature in that (89) a magnetic storage system having a magnetic head and a magnetic recording medium combined for reading or writing a magnetic signal as data source mentioned above wherein the magnetic recording medium has a zigzag series of recorded bits aligned thereon and in a reading or writing mode of operation, the magnetic head and the magnetic recording medium are alternately moved in a simple harmonic motion; (90) the magnetic storage system of item 89 mentioned above wherein the magnetic head is a multi-head having a plurality of read/write devices regularly aligned on a plane; (91) the magnetic storage system of item 89 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the track width direction; (92) the magnetic storage system of item 89 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic head in the recording bit direction; (93) the magnetic storage system of item 89 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic head in the recording bit direction and the track width direction; (94) the magnetic storage system of item 89 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the recording bit direction and a one-dimensional motion of the magnetic recording medium in the track width direction; (95) the magnetic storage system of item 89 mentioned above wherein seeking is made by combination of a one-dimensional motion of the magnetic head in the track width direction and a one-dimensional motion of the magnetic recording medium in the recording bit direction; (96) the magnetic storage system of item 89 mentioned above wherein seeking is made by a one-dimensional motion of the magnetic recording medium in the track width direction; (97) the magnetic storage system of item 89 mentioned above w herein seeking is made by a one-dimensional motion of the magnetic recording medium in the recording bit direction; (98) the magnetic storage system of item 89 mentioned above wherein seeking is made by a two-dimensional motion of the magnetic recording medium in the recording bit direction and the track width direction; (99) the magnetic storage system of item 89 mentioned above wherein a piezo device prompts a reciprocal motion of the magnetic recording medium or the magnetic head in the recording bit direction in the reading or writing mode of operation or prompts a motion of the magnetic head or the magnetic recording medium among adjacent elements of the magnetic head in the track width direction in a seeking operation; (100) the magnetic storage system of item 89 mentioned above wherein the magnetic recording medium is a square or polygon and has regular grooves formed on a surface thereof; (101) the magnetic storage system of item 100 mentioned above wherein the magnetic recording medium is formed on a Si substrate of single crystal and the regular grooves are formed by way of a chemical etching process with use of a crystalline orientation; (102) the magnetic storage system of item 100 mentioned above wherein the magnetic recording medium is for longitudinal magnetic recording or perpendicular magnetic recording and for the longitudinal magnetic recording, an easy axis is in parallel with the recording bit direction; (103) the magnetic storage system of item 89 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is based on position information written in between sectors of a single track; (104) the magnetic storage system of item 89 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is made in a way that the magnetic head has a semiconductor laser on a part thereof, a laser beam is incident on a surface of the magnetic recording medium, and a difference of a light emission condition of the semiconductor laser with presence or absence of a groove is converted to voltage change or a change of light intensity at a rear of the laser is detected; (105) the magnetic storage system of item 89 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation in a way that the magnetic head has at least one detecting needle mounted thereon, and at least one detecting needle is brought close to a surface of the magnetic recording medium to detect a change of a tunneling current with presence or absence of a groove; (106) the magnetic storage system of item 89 mentioned above wherein positioning the magnetic head or the magnetic recording medium in the track width direction in a seeking operation is made in a way that a number of grooves on a surface of the medium is counted on the basis of a change of an emission condition of a semiconductor laser or a tunneling current with the magnetic head or the magnetic recording medium moving in the track width direction; (107) the magnetic storage system of item 89 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is controlled with use of at least one piezo device; (108) the magnetic storage system of item 89 mentioned above wherein a contact force of the magnetic head with the magnetic recording medium is different, or higher in the reading or writing mode of operation than in a seeking operation; (109) the magnetic storage system of item 89 mentioned above wherein a volume of the magnetic recording medium is not greater than 40 cc; (110) the magnetic storage system of item 89 mentioned above wherein a single set of the magnetic head and the magnetic recording medium has data transferred therein in parallel; (111) the magnetic storage system of item 89 mentioned above wherein a multiple of sets of the magnetic heads and the magnetic recording media have data transferred thereamong in parallel; (112) the magnetic storage system of item 89 mentioned above wherein a mean access time is not longer than 1 msec; and (113) the magnetic storage system of item 89 mentioned above wherein a transfer rate is not slower than 30 Mbyte/sec.
The reading or writing mode of operation and the seeking operation are different from each other with respect to the contact force of the read/write device with the magnetic recording medium. The problem mentioned above can be overcome in the way that the recording medium or the read/write device is driven by, for example, the piezo device, the relative motion of the head to the medium is made reciprocal, the linear or circular or zigzag aligned recorded bits are formed on the surface of the recording medium, and the recorded bits are read by the read/write device. The reciprocal motion mentioned above can be accomplished in the way that the read/write device or the recording device or the both are driven by the piezo device, the quartz crystal, or similar devices for converting the rotational motion to reciprocal motion. The magnetic head used is of multi-head type which has a plurality of read/write elements regularly formed on the plane, and the read/write elements and the recording layer of the recording medium are formed on a single-crystal Si substrate. It is preferable that the surface of the substrate to have the magnetic recording medium formed thereon has regular grooves formed in parallel with the recorded bit directions. The grooves can be formed by a chemical etching process in which the crystalline orientation is used. Positioning the magnetic head or the magnetic recording medium in the track width direction in the reading or writing mode of operation is made in a way that the magnetic head is provided with a semiconductor laser on a part thereof, a laser beam is incident on a surface of the magnetic recording medium, and a difference of a light emission condition of the semiconductor laser with presence or absence of the groove is converted to voltage change or a change of light intensity at a rear of the laser is detected. Alternatively, the positioning mentioned above can be made in a way that the magnetic head is provided with at least one detecting needle mounted thereon, and the at least one needle is brought close to a surface of the magnetic recording medium to detect a change of a tunneling current with presence or absence of the groove. Positioning the magnetic head or the magnetic recording medium in the track width direction in a seeking operation is made in a way that a number of the grooves provided on the surface of the medium is counted on the basis of a change of an emission condition of the semiconductor laser or a tunneling current with the magnetic head or the magnetic recording medium moving in the track width direction. The contact force of the magnetic head with the magnetic recording medium is controlled with use of the at least one piezo device. The contact force of the magnetic head with the magnetic recording medium is controlled so that it is higher in the reading or writing mode of operation. With combination of the processes mentioned above, we can construct the storage system so that its volume is not greater than 40 cc, data can be transferred in a single set of the magnetic head and the magnetic recording medium in parallel, or more preferably data can be transferred in a multiple of sets of the magnetic heads and the magnetic recording media in parallel, a mean access time cannot be longer than 1 msec, and the transfer rate cannot be slower than 30 Mbyte/sec.
With the relative reciprocal motion of the head to the medium, the magnetic recording medium can be shaped to a desired polygon. This means that the storage system cannot be easily made small, but also constructed to a desired shape. If the reciprocal motion of the recording medium or the head is prompted by, for example, the piezo device, high-speed data transfer can be made. If the piezo device is set to 200 xcexcm stroke, the frequency is set to 50 kHz, and each sector of the data is set to have 256 bytes, with the magnetic recording method used, then it is possible to transfer of the data of 25 Mbyte per second. The recording data line density required is about 200 kFCI (kilo-flux changes per inch). This can be accomplished even in the longitudinal or perpendicular magnetic recording method if the spacing between the head and the medium can be made narrow to around 0.05 xcexcm in the reading or writing mode of operation. If the multi-pattern head having the plurality of the read/write elements regularly aligned on the plane is used as the magnetic head, it can read the data from a plurality of the tracks at a time. This can further increase the data transfer rate. If a head operating area in a single reading or writing operation is limited to a narrow one, seeking can be made without moving the head. This extremely shortens the seek time because no mechanical motion involves the seeking operation.
On the other hand, if the substrate of Si single crystal is used for the medium, the regular grooves and the like can be processed at high accuracy by way of the chemical anisotropy etching process with use of its crystalline orientation. If the very smooth surface of the Si substrate also is used for the head, the spacing between the head and the medium in the reading or writing mode of operation can be kept very narrow. This is advantageous for accomplishing the high-density recording. If Si is used for the head substrate, it is possible to form the preamplifier on the plane opposite to the head device or similar ones by way of the photo-lithography process. This further facilitates making the storage system small. An accuracy of the simple harmonic motion of the head or the medium can be made very high in the way that the semiconductor laser is mounted on the part of the magnetic head to make the laser beam incident to the surface of the regularly aligned grooves, and the emission condition and the similar ones are monitored to always control the laser beam.